Employees and supporters demonstrate Monday outside of a Wendy's fast-food restaurant in New York City to demand higher pay and the right to form a union. Incomes have been stagnant, especially for minimum-wage workers.

According to the national study, more than half of fast food workers have to rely on public assistance programs to provide for their families and afford health care because their wages, which average $8 an hour in California, aren't enough to support them.

The public aid carries a $7 billion price tag for taxpayers each year, according to the report.

In August, fast-food workers in San Diego and across the nation staged a one-day strike to call for an increase in the minimum wage to $15 an hour and the right to unionize.

San Diego Fast-food workers and community leaders are planning a news conference Tuesday morning at an area McDonald's restaurant to discuss the findings of the study.